Removed CONFIG_LIBC_ARCH_BZERO.  bzero() is a deprecated interface.  There are no architecture-specific replacements and, if there were, they should replace memset(), not bzero().

This should resolve issue #30: Audio Tone Generator and PWM Multiple Output Channel options.  I don't actually have a setup to verify it, however.

STM32F7 has up to 128KiB of DTCM memory that is currently left unused.

This patch adds DTCM to main heap if CONFIG_STM32F7_DTCMEXCLUDE is not enabled.

Add twr-k64f120m config and fix some ENET related problems

Approved-by: Gregory Nutt

Add driver for the ST L3GD20 3 axis gyro

Approved-by: Gregory Nutt

Allow board to configure HSE clock in bypass-mode. This is needed to enable HSE with Nucleo-F746ZG board.

LM3S Ethernet: Fix interrupt work in the last big commit.

Approved-by: Gregory Nutt